<div class="grid-container">
  <div class="grid-item" style="background-color: red;">1</div>
  <div class="grid-item" style="background-color: green;">2</div>
  <div class="grid-item" style="background-color: blue;">3</div>
  <div class="grid-item" style="background-color: yellow;">4</div>
  <div class="grid-item" style="background-color: pink;">5</div>
  <div class="grid-item" style="background-color: orange;">6</div>
  <div class="grid-item" style="background-color: purple;">7</div>
  <div class="grid-item" style="background-color: brown;">8</div>
  <div class="grid-item" style="background-color: grey;">9</div>
</div>

<style>
  .grid-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    grid-gap: 10px;
    grid-auto-flow: row;
    width: 95vw;
    height: 95vh;
  }
</style>
